A condition where fecal matter gets on your nutsack after taking a nice healthy shit and then wiping your ass from back to front.
That shit on your underwear doesnt look like skid marks, i bet its from mudnuts!!!
Fecal matter mixed with semen in the anus. Primarly used at scat parties. (aka: shemen)
Before arriving at his bi-weekly scat party, jaay mixed up a fresh batch of mudnut in his anus.